Fuzzy Modeling and Interior Point Algorithm of Multi-objective OPF with Voltage Security Margin

According to the fact that current power system operation trends towards its stability limit, a multi-objective optimal power flow (OPF) formulation with voltage security margin is presented in this paper, which optimizes the total generation cost while ensuring the system to operate within its ideal loading margin. The multi-objective OPF formulation is then reformulated using fuzzy modeling approach in order to overcome the drawback of "weighting method" objective function and all constraints treated as hard constraints. In addition, the necessity of determining appropriately ideal loading margin region is proposed in order to guaranteeing the secure and economic operations of power systems. This study is made in the system for a linearly increasing, constant power factor load model. The nonlinear predictor-corrector primal-dual interior point method is used to solve this optimization problem. Test results show that this formulation can effectively determine the optimal secure loading point and find the infeasible loading point of power system, given the ideal loading margin region. And the main factors that have impact on the optimal generation cost of power system are also presented by analyzing the results